The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
A “mobile device” generally refers to a computing device having user interface, a display, and a processor. For example, the mobile device may be a mobile phone, tablet computing device, global positioning system transceiver, and the like. Mobile devices may selectively connect to a network such as the Internet and/or a mobile telephone network. A user may input information, e.g., text, to the mobile device via a user interface (or “character layout”) such as a keyboard and/or a number pad. Due to size constraints, however, mobile devices may include a partial QWERTY-based physical keyboard. Additionally or alternatively, mobile devices may include touch displays, e.g., capacitive sensing displays, which both display information to the user and receive input from the user. For example, these mobile devices may display a character layout to the user similar to the partial QWERTY-based keyboard or number pad.
Mobile devices are increasingly being used to store and access sensitive user data. For example, users may store passwords and/or account numbers on their mobile devices. In another example, users may use their mobile devices to access healthcare records, bank accounts, internal corporate emails, and other highly private records. It is not a secret that there are malicious interlopers who wish to obtain sensitive user data by accessing these mobile devices, or to intercept the sensitive user data as it is being transmitted over a network. These interlopers use various techniques to obtain the sensitive user data stored in the mobile device. One such technique that an interloper may implement is to monitor an accelerometer signal outputted by an accelerometer of the mobile device to determine a location at which user input was provided.